Shaders Help with setting up alpha to 0 in just some pixels?

[theraje3]

So, Im having a really hard time trying to make this happen, so I just decided to ask for help :3.

• What I want to achieve:

I have a large rectangular sprite, and I want to make it invisible X pixels from de left to the right. I already have the X value set up with an uniform.​

• Why I'm suffering:

I can't get just X number of pixels from the left to the right to make them invisible (and only those) I only get the full sprite or noone...
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• What I think I need:

I need the selection of those pixels, I imagine using a vec2 with the .x value and modifing or making a new v_vTexcoord.
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Any ideas of how can I do that? thx for reading and sorry for english!!

 

[NightFrost]

If a partial sprite draw is all you require, you could use draw_sprite_part() instead of writing a shader.

 

[theraje3]

woah thanks a lot... searched for a similar function but I didnt find it so I tryied make it in the shader.... you just made my life much easier. thx!!

(anyway if someone knows how to do that in shader aswell would be great)